Gear shifting mechanism



Aug. 20. 19 R. N. VAN BUSKIRK GEAR SHIFTING MECHANISM Filed May 20, 1937 10 Sheets-Sheet l 1N VEN TOR.

ATTORNEY.

Aug. 20, 1940. R. N. VAN BUS KIRK r 2,212,282

GEAR SHIFTING' MECHANISM Filed May 20, 1937" 10 Sheets-Sheet 2 ATTORNEY 20, 1940- R. N. VAN-BUSKJRK 2,212,282

GEAR'SHIFTING MECHANISM Filed May 20, 1957 10 She ets-Sheet :5

INVENTOR.

ROBERT /V. VANBUGKIRK ATTORNEY.

Aug. 20, 1940. R VAN B QR 2,212,282

I GEAR SHIFTING MECHANISM Filed May 20, 1937 10 Sheets-Sheet 4 I v INVENTOR. fig. 5'5 FCBERT N Mq/vBmsK/mr ATTORNEY.

Aug. 20, 1940.

R. N. .YVAN BUSKIRK GEAR SHIFTING MECHANISM Filed May 20, 1937 10 Shama s-Sheet s mum INVENTOR. fier N MINBUGK/RK A ORNEY.

20; 1940- R. N. VAN BUSKIRK 2,212,282

GEAR SHIFTING MECHANISM Filed'May 20, 1937 10 Sheets-Sheet 6 VENTOR. fj 57. 15 m ROBERT M I/ANBUsK/RK ATTORNEY Aug. 20, 1940. R. N. VAN-BUSKIRK GEAR SHIFTING MECHANISM Filed May 20, 1937 10 Sheets-Sheet 7 INVENTOR. I ROBERT N MMYBUSK/R/f ATTORNEY.

Aug. 20. 194 R. N. VAN BUSKIRK GEAR SHIFTING MECHANISM Filed May 20, 1937 10 Sheets-Sheet 8 IIIIIIIIIII Ill/I INVENTOR. 7 ROBERT A/ Mfl/YBUK/RK ATTORNEY.

Aug. 20, 1940. R N. VAN-BUSKIRK GEAR SHIFTING MECHANISM Filed May 20. 1957 10 Sheets-Sheet 9 Aug. 20, 1940. R. N. VAN BUSKIRK 2,212,282

GEAR SHIFTING MECHANISM Filed May 20, 1937 10 Sheets-Sheet 10 l/ /Z4- 3 [Z5 INVENTOR.

BY'WW ATTORNEY Patented Aug. 20, 1940 Q UNITED STATES GEAR smrrmo MECHANISM Robert N. Van Buskirk, Detroit, Mich, assignor to Bendix Products Corporation, South Bend, Ind., a corporation of Indiana Application May 20, 1937, Serial No. 143,705

Claims.

This invention relates to improvements in speed change mechanisms for motor vehicles and more particularly to improvements in the construction and operation of the conventional speedchange 5 transmission rendering the same operable by either a selective finger controller or automatically in response to the speed of the vehicle.

An important object is to improve the operation of the speed change mechanism between the power unit of the motor vehicle and the driving road wheels. As a result of this invention, the use of a conventional gear shift lever is eliminated and-in its place a semi-automatic or full automatic controller may be substituted. Another l5 object of this invention is to provide an improved gear shifting'mechanism for the speed change transmission which is strong, rugged and easily operated and which may be installed or incorporateg in the conventional transmission without radically altering the construction thereof.

Another important-object of this invention is to combine the improved gear shift mechanism with the clutch operating parts in such a novel way that the shifting operation is effected when the clutch parts are operated thus doing away.

with the need of a separate power unit for accomplishing the gear shifting operation. Another objectv of this invention is to provide :novel manual, vacuum power, or automatic vehicle speed controllers for regulating the gear shifting action inthe transmission. Dual optional control of the shifting mechanism may be effected between the various forms of controllers, such as between the manual control through the clutch pedal and the vacuum control by means of a. vacuum power unit or between the power and fully automatic vehicle speed controller. When power means is employed to shift the gears, novel connecting means may be employed which operate the gear shifting through clutch operating parts but not including" the clutch pedal so that the latter is not moved when the shifting operations are performed. Dual manual and power control over the shifting operation insures 5 positive manual operation in the event of failure of the power operating means.

A meritorious feature of the invention is found in the pre-selecting mechanism which is capible of selecting the desired speed change at anytime,

5o irrespective of whether the transmission elements are already engaged or whether the vehicle is moving or standing still. This simplifies driving in city traflic since it is possible'to select any gear change without progressively going through 55 the gear changes leading to the desired selection.

When manual control is exercised over the gear shifting, such as through the clutch pedal, there is no need of synchronized manual action between the gear change selection and the acceleration of the motor or between the gear change 5 selection and the clutching operation.

A still further object of the invention is to provide an improved speed change mechanism which is completely automatically responsive to all forward speeds of the motor vehicle. Pro- 10 vision is made for either manual or fully automatic control. When automatically controlled, novel means is provided for indicating to the driver all the forward speeds automatically selected by the speed of the motor vehicle. 15

Various other objects, advantages and meritOllOLS features of my invention will appear more fully in the following description, accompanying drawings and appended claims, wherein:

Fig. 1 shows a side elevation of a portion of a 20 conventional automobile indicated in dotted lines, with my invention and component parts applied thereto in a schematic manner.

, Fig. 2 is a similar illustration of a portion of and viewed from the right of Fig. 1, 5

Figs. 3 and 4 show a plan and elevation respectively of the selecting means Figs. 5 and 6 are fragmentary views of a portion of Fig. 1 illustrating optional methods of operating the clutch and shifting mechanism.

Fig. v'7 is a diagrammatic view showing the vacuum control elements positioned for one stage of contro1, with an enlarged detail of the vacuum control valve.

Figs. 8 and 9 are views similar to the above, showing two other stages of the clutch throw-rout shaft control.

} Fig. 10 isa longitudinal section of the shifting mechanism applied to a conventional transmisa sion, taken on line Ill-l0 of Fig. 11. v 40 Figs. 11 and 12 are plan sections as indicated by lines ll-ll and l2-I2 respectively in Fig. 10.

Fig. 13 is aside elevation of Fig. 12, partly broken away.

Fig. 14 is a sectional view taken on line ll-ld of Fig. 12.

Fig. 15 is a sectional plan taken on line li-l of Fig. 14, showing the shift rods in positionfor low" speed.

Figs. 16 and 17 are sectional elevations indicated by lines 16-46 and ll-l'! respectively, in Fig. 12.

Fig. 18 is a perspective of the shift rod operating frame. 66

Figs. 19 and 20 are perspectives of one of the selecting members.

Figs. 21, 22 and 23 are fragmentary sections taken on line 2l2l of Fig. 11, illustrating sequential positions of the selecting and shifting members.

Figs. 24 and 25 are fragmentary sections corresponding to Figs. 10, 13 and 23, illustrating a modified means of selecting.

Fig. 26 is a fragmentary plan of the shift rod frame shown in Fig. 24, partly broken away.

Figs. 27, 28 and 29 are sectional views illustrating the manual selecting means for the modification shown in Fig. 24.

Fig. 30 is a schematic illustration corresponding to Fig. 1, showing an automatic control modification for the shifting mechanism.

Fig. 31 is a plan view of a portion of Fig. 30.

Figs. 32 and 33 are sectional views as indicated by lines 32-32 and 33-33 respectively in Fig. 31.

Fig. 34 is a detail section of the modified control valve. I

. Fig, 35 is a detail section of the vacuum cylinder valve used in both of the vacuum control systems.

Figs, 36, 3'7, 38 and 39 are diagrammatic views showing the various relational positions of the control valve and operating elements of the modification shown in Figs. 30 and 31.

Fig. 40 shows a modified clutch pedal and throttle rod.

In the drawings, Figs. 1 to 6 inclusive, conventional automobile motivating elements are shown mostly in dotted lines, and designated as a motor a, crank shaft b, clutch shaft c, clutch throw-out sleeve (1, clutch spring e, clutch throw-out shaft j, clutch pedal 9, clutch case h, transmission final drive shaft 1', transmission case 1', chassis frame 70, fuel intake manifold l, throttle lever m, back stop 11-, throttle rod 0, accelerator pedal p, steering column q, instrument panel 1', and brake pedal s.

The conventional transmission structure shown in Fig. 10 operates in the usual manner, wherein the rearward movement of the shift fork t causes the sliding gear u, splined on the shaft 1, to en-' gage with the idler pinion-u for reverse drive. Forward movement of the fork t causes the gear u to engage the auxiliary shaft gear 2 for low speed ahead. The shift fork :1: moved rearwardly causes the gear clutch member 1/, also splined on the shaft 1', to engage with the constant-mesh gear w for intermediate speed. Likewise when the fork a: is moved forwardly the clutch member 11 engages the constant-mesh gear integral with the clutch shaft 0, thereby effecting a direct drive for "high" speed.

For the purpose of clarity the principle of the gear shifting mechanism will be described first since substantially the same principle is utilized in all the modifications of the invention described herein.

The shifting mechanism indicated generally as 40 in Figs. 1 and 2, and as shown in detail in Figs. 10 to 23 inclusive, comprises a sub-case 4| and a cover 42 bolted to the transmission case 7',

within which the shift rods 43, 44, 45 and 46 reciprocate axially in the bearings 41 clamped between the walls of the cases :i and 4l. The shift forks t and :c are fixedly attached to the middle shift rods 44 and 45 respectively. Gears 4! journaled on studs 49 attached to the plate secured to the case j, mesh with rack teeth 5| on the shift rods, one gear between the shift rods pair of shift rods together so that when one rod is moved the other rod of the pair is moved an equal distance in the opposite direction, The rod pair 43 and 44 cooperate in shifting the fork t for reverse and low speeds, and the rods 45 and 46 cooperate in shifting the fork a: for intermediate" and. high speeds.

Also mounted on the plate 50, between the rods 44 and 45, is a split bracket 52, within which is positioned a two-piece spring expanded dog 53, which in addition to serving as a detent in notches 54 when one rod is shifted, also interlocks with and withholds the opposite rod from movement, byvirtue of the limited clearance 55 between the expanding halves of the dog,

For shifting the rods to alter the gear relationship in the transmission, a rectangular frame member 56, shown complete in Fig. 18, encloses the middle sections of the shift rods and is adapted to be reciprocated axially on the rods, the opposite ends of which extend through perforations 51 in both end walls of the frame. The front end wall 58 has a turned up retaining flange 59 having guideways B0 in alignment with the perforations 51. The front wall 58 also has a horizontal flange portion- 8| extending forwardly, having perforations 62 also in alignment with the perforations 51. Attached substantially in the middle of the side walls of the frame 56 are trunnion pins 11. The rear wall I'll] of the frame is adapted to abut against shoulders I'll to I14 carried by the shift rods as will be more fully described hereinafter.

A selecting shift rod locking device or dog 63 is illustrated in Figs. 19 and 20, one of such dogs being used for each shift rod. The purpose of these dogs is to releasably lock any one of the shift rods 43, 44, 45 and 46, with the rectangular frame for joint movement therewith. Each dog has a perforation 64 through which a shift rod extends. The four dogs each have an integrally formed horizontal tappet portion like that shown at 56 in Figs. 19 and 20. These tappets are arranged to cooperate with the shift rods 43, 44,

45 and 46 and are numbered 66, 81, 68 and 69 respectively. The dogs are retained in a row in juxtaposition with the inner side of the frame wall 58 by the frame flange 59 and the depending tappet studs 10 which are adapted to reciprocate vertically in the frame flange apertures 62. The dogs are permitted vertical movement but are restrained from rotative movement by means of the dog lips 65 which are adapted to reciprocate vertically in the ways in the flanges 59.

Springs II are disposed about the studs 10 of each shift rod dog and interposed between the flange SI and the tappet portions of the dogs. The springs urge the dogs upwardly and hold the bottom straight edges 12 of the dog perforation 64 up against the underside of the shift rods. The bottom edges 12 may extend into the notches 13 provided on each shift rod when the latter has been moved to a predetermined position relative to the rectangular frame as shown in Figs. 21' and 22.

The rectangular frame 56 is mounted for movement parallel to the movement of the shift rods. Means for moving the frame comprises a transversely extending shaft 14 surmounting the frame and rotatably supported in bearings 16 clamped between the case 4| and cover 42. Trunnion arms 15 keyed to the shaft 14 are spaced to straddle the shift rods and extend downward to engage the shift frame trunnion pins I1. This construction is probably best shown in Fig. 17.

To rock the shaft 14 and thus swing the frame 58, a gear sector I8 (see Fig. 13) is keyed to the outside end of the shaft 14 which extends outside of the case. This gear sector engages the toothed rack portion 19 of the shift frame operating rod 88 which is slidable axially within the bearings 8I of the case, in parallel relation to the inside shift rods. The rod 88 is provided with a right and left hand threaded turnbuckle 82, for pick-up adjustment of the rack teeth 19. The rod also has a clevis eye 83 at the forward end through which a pin 84 extends, engaging a slot in the operating lever 85 which is keyedto the clutch throw-out shaft 1 Selector control mechanism for determining the gear change in the transmission comprises a rotatable selecting cam member 86 of a cylindrical form located above and at right angles to the shifting rods and substantially over the aforesaid dog tappets. The member 88, as shown in Figs. 12 and 16, is assembled within the bearings 9| which are clamped between the case and cover. The cam member has milled off fiat cam faces Ill, 88, 89 and 90 spaced along its axis in alignment with the shift frame tappets 86, 61, 88 and 69 respectively. These cam faces are also spaced in predetermined angular relation about'the periphery of the member 86.

For rotating the cam member 86 and thereby successively bringing the flat cam faces 81, 88, 89. and 90 into contact with their respective dog tappets a pinion 92 is fixed on one end of the cam member within the case and gear sector 93 is meshed therewith. The gear sector 93 is attached to the spindle 94 which extends through the side wall of the case 9', and is journaled in the case bearing 95. A sector operating lever 96 is keyed to the spindle 94 outside of said case, this lever being secured by the pin 91 to the connecting rod 98 which extends forwardly and upwardly in a plane substantially at right angles to the steering column q.

Referring to Figs. 1 to 6 inclusive, the rotating selector member 88 in the transmission housing may be remotely controlled by a manual control mechanism comprising a shaft 99 located in parallel relation, and adjacent to the steering column and tT e connecting rod 98 extending at right angles thereto and connected to the selector member through lever 96 as previously described. Shaft 99 is disposed between a bearing bracket I00 which is attached underneath floor boards IIII, and a selector bracket I82 which is secured to the upper portion of the steering column adjacent the steering wheel by a clamp I83. The lower end of the shaft 99 has fixedly attached thereto a lever I04 which is connected to the forward end of a connecting rod 98 by a ball joint I05. The upper end of shaft 89 is journaled in a bearing I06 in bracket I02, and is pinned to a manual selecting armIIII positioned underneath a selector bracket I88. Arm III! has a portion is freely journaled on the clutch throw-out shaft and carries an integral depending pick-up arm II I. A second depending pick-up arm IIZ, having an extended integral lever H3, is also freely journaled on shaft 1'. A third arm H4 is positioned between the pick-up arms III and H2 and is keyed to clutch shaft f in the same manner as the shifting mehcanism lever 85, whereby both members, I I4 and 85 operate in unison with the clutch throw-out shaft f and sleeve d. Arm II4 has a broadened extremity with which the pick-up arms III and H2 are adapted to register and abut. When the clutch pedal is depressed, pick-up arm ill engages the broadened portion of arm H4 and swings the latter and shaft therewith.

The apparatus previously described is an entirely manually controllable gear shifting mechanism wherein movement of the clutch pedal is adapted to shift the gears inthe transmission and wherein a finger controlled speed selector on the steering wheel column is adapted to control type of gear shifting which movement of the clutch pedal will impart. As has been previously mentioned, the shifting mechanism thus far described may be associated with a vacuum power device or a fully automatic device controlling the gear change by the speed of the vehicle. These modifications will be described hereinafter. At present the operation of the entirely manual control gear shifting mehcanism will be described.

Movement of the clutch pedal 9 back and forth will impart reciprocal movement to the rectangular frame 58 in the transmission housing. Movement of the control handle I01 adjacent the steering which will cause rotation of the selector cam member 88 in the transmission housing. These movements are obvious from the operating connections between these elements previously described. A lost motion provision is made between the movement of the clutch pedal and the movement of the shift rod frame 56. When the clutch pedal is in raised or clutch engaged posi- 'tion the rack teeth 19 on connecting rod 80 are spaced slightly from the gear sector I8. Initial movement therefore of the clutch pedal will not cause a corresponding movement of the frame 56. This lost motion is so regulated that after the pedal has been moved far enough to disengage the clutch, the rack teeth 18 mesh with the teeth on the sector and commence moving the frame 56 forwardly proportionately to the depression of the clutch pedal.

In Figs. 11 and 12, the elements in the transmission housing are in neutral position. The shift rods 43 to 46 are disposed equally opposite one another and the cam member 86 is so positioned that none of the flat faces 81, 88, 89 or 90 are disposed opposite their dog tappets so that'all the locking dogs are held down in unlocking position against the tension of their coil springs II. Shift rods 43 and 44 function to shift gears for "reverse and "low speeds. Shift rods 45 and 46 function to shift gears for "intermediate and high speeds. To shift the gears in the transmission into low" or first speed; the fork t as previously explained must be moved forwardly to cause the gear u to engage the auxiliary shaft gear z. Since the fork t is attached to the shift 7 rod 45, this rod therefore must be engage the gears for low speed.

To accomplish a change in the transmission from neutral to low" speed, the selector arm I81 on the steering column is moved until it is opposite the notch designated as numeral "1". This movement will rotate cam member 86, by means heretofore described, in a clockwise direction from the position shown in Fig. 10 to that shown in Fig. 22, bringing cam face 81 above and parallel to tappet face 66. This tappet is integral with locking dog 63 on shift rod 43. Spring H is tending to raise this dog up but the bottom edge 12 of the rod aperture in the dog is withheld against the undersideof the shift rod 43 as Fig. 22 indicates. The clutch pedal is now completely depressed causing the rectangular frame 56 in the transmission housing to move forwardly, by means heretofore described connecting the clutch pedal to the frame, until the rear wall I18 of the frame abuts the shoulders I1I to I14 of the shift rods. Since all four locking dog devices 83 are attached to the front wall 58 of the frame, they will all move longitudinally along the shift rods in unison with the frame until the bottom edges 12 of the rod apertures in the dogs appear opposite the notches 13 found in each shift rod. At the end of this frame stroke, the dog which is free for upward movement, which in this instance is the dog having the tappet 66, will rise vertically and the edge 12 will latch or interlock with the notch 13 provided in the shift rod. Since only one fiat face on the cam member 86 can register with a tappet at one time, the other locking dogs are restrained from upward movement by the cylindrical surface of the cam member, thus preventing the dog portions 12 from entering the rod notches 13 when they are brought into alignment at the end of the forward stroke of the shift frame.

As the dog having tappet 86 is now interlocked with the frame, the return movement of the moved to clutch pedal will shift the frame and shift rod 43 rearwardly in unison. By virtue of the'pinion 48 and the rack teeth engaging therewith, the rearward motion of shift rod 43 will cause an equal forward motion of the shift rod 44 and its attached shifting fork t. Gear u will thereby mesh with low speed gear 2 and the transmission has been shifted into low speed. The meshing of these two gears, as well as any other gears in the transmission, takes place before the clutch pedal has fully returned to its raised position and before clutch engagement is effected by reason of the lost motion connection previously described between the rack teeth 18 and the ear sector 18.

In the case of reverse speed, where it is only necessary to move shift rod 44 rearwardly for engagement of gears u and 12, this rod is actuated directly by the dog of tappet' 61, its companion shift rod 43, merely being idled forwardly by pinion 48. The selecting and shifting for the two forward speeds, intermediate and high,

of the frame will be stopped when the rear wall I10 of the frame abuts all four shoulders I'll to I14 on shift rods, inasmuch as the forward and rearward pressures are equalized on alternate shoulders of the shift rods. The shift rods are now in neutral position but the frame is at the end of its forward stroke. The condition of the cam member 56, as predetermined by the selector handle I01 will allow that tappet to rise which will cause shifting to second speed upon rearward movement of the frame. In the present embodiment of the invention this is the tappet 68 which is associated with shift rod 45. Return movement of the clutch pedal, as effected by expansion of clutch spring e acting through clutch sleeve d and shaft J, will cause shift rod 45 and associated fork :v to move rearwardly and cause the gear clutch y to engage with constant-mesh gear 10 for intermediate speed.

It is apparent. therefore that any forward stroke of the frame 56 will pick up a rearwardly positioned shift rod and return it and its forwardly positioned companion shift rod to normal or neutral position. -It is also apparent that the frame would move rearwardly Without carrying a shift rod therewith unless one of the latchingdogs 63 had been preselected for locking engagement with its respective shift rod.

It is also clear by comparison of Figs. 21, 22 and 23 that the tappets 66 to 69 never move beyond contact with the cam member 86. Therefore any dog already engaged with a rod may be disengaged from the rod while the latter is in either forward or rearward position. It is obvious from the foregoing description, progressive" speed selecting is not required, but that any speed desired may be selected, depending, of course,

upon the physical factors-involved at that time. Speed selections, such as the following, may be made; from high to low as on a hill; from low to high" on the level or downgrade; and when starting, from high to reverse" or from neutral to intermediate.

.A modified form of manually controlling the selector member 86 is shown in the drawings in Figs. 24 to 29 inclusive. These figures di. .lose a modification of the foregoing selecting elements, wherein control buttons R, N, L", I" and H", corresponding to reverse, neutral", low, intermediate" and high respectively, are depressed manually to actuate the selecting elements within the shifting unit. The push buttons are attached to plungers I11 which reciprocate in apertures in the case I18 and plate I19. The button control unit may be mounted on the dash panel or upon the steering column. The four plungers actuate bell cranks I80 pivoted at I8I. Bowden wires I 82 areattached to said cranks and extend through flexible conduits I83 secured at one end to the case I18 and at the other end to the control housing 4 I on the transmission. v

The plungers have integral cam portions I84 normally held against the inner surface of case I18 by springs I85. The cam plate I86 has cam lips I81 bent outwardly. The plate is positioned within ways I88 and held in a retracted position abutting the case wall by springs I88 which engages notch I90 in said plate. When a plunger is pushed in, the cam I84 will bear against .the lip I81 and" force the plate to the right. When the cam passes the lip the plate will snap back to the left by virtue of the spring I88. and the plunger will be thus withheld in retracted position by the abutment of the cam portion I84 with the back end of the plate lip, as shown at Ifby plunger in Fig. 28. When a succeeding speed is to be selected, high for instance, the depression of the H plunger will cause its cam to bear against the corresponding lip and again impart ,a lateral movement to plate I86,

and release the I plunger cam as the H plunger cam and lip engage. The N plunger only functions to release other plungers for neutra The selector wires I82 extending within transmission control case M are each attached to U shaped stampings I9I having inclined slots I92 in the sides thereof, positioned within inverted U shaped members I93 attached to the top wall of the housing. Each inverted U shaped member E93 has a transverse pin I94 secured in the side walls thereof and extending into the inclined slots I92 upon which members I9I are adapted to reciprocate. A pair of such slot and pin combinations on each side of the members' l9I serve to direct these members in a given path corresponding to the inclination of the slots. A spring 2I2 yieldingly urges each member I9I' to a retracted inoperative position as shown in Fig. 24, where the bottom face I95 of said member serves to restrain movement of selector pawl I96. Four such selector pawls corresponding in numher and position to the shift rods are pivoted on pins i9? secured in lugs on the front wall flange 6I' of shifting frame 56. Dogs I98 loosely pinned at W9 to the pawls, are piloted vertically through apertures in flange 6|. Coiled springs 206' about each pivot I97 yieldingly urge the dogs I98 downward.

In selecting, by depressing a plunger at the instrument panel, the corresponding wire and member I9I are pulled forward, the latter being also moved upward by means of the inclined slots guided on pins I94, to the position shown in Fig. 25. This movement will free the pawl I96, and when the shift frame 56' is moved forwardly the spring 200 will urge dog I 98 to latch into the rod notch 73, interlocking the rod and frame for joint movement, as heretofore described.

The rod shifting frame 56' by a modified form I 208 is pivoted to lever 205 at 209; the other end.

has a slot 2I0 for over-running action on a pin 2il in the bifurcated lever 85', which is integral with the clutch throw-out trunnion, located directly above the center of the clutch throw-out shaft f.

At the end of the first portion of the forward movement of the lever 85', when the clutch becomes free, the pin 2 will pick up at the end of the link slot 2 I and pull the shift frame forward, thereby permitting dog I98 to engage rod notch I3. Upon the return stroke of lever 85', said lever and shift frame will move rearwardly in unison until the clutch again starts to engage, during which movement the frame is shifted by means of the spring 202, after which the lever pin 2 will idle back in link slot 2") while the clutch comes into full engagement.

When a selecting plunger is released, the connecting wire I82 and member I9I are pushed back to the positionin Fig. 24 by means of the plunger spring I85, member I9I being further urged downwardly by spring 2I2.

As previously mentioned, the gear shifting operation may be performed by a novel vacuum power device. This device may be associated with the gear shifting mechanism alone or in dual optional relationship with a manual means of shifting gears. In Figs. 1,7, 8 and 9, there is a vacuum power device optionally associated with the clutch operated shifting mechanism previously described. The vacuum power device comprises, in general, a vacuum operated piston having operative connections through the clutch shaft with the rod shifting frame hereinabove described and separate valve control means associated with the piston and with the accelerator mechanism of the motor vehicle for controlling the operation of the vacuum power device.

Referring in detail to Fig. 1., a vacuum cylinder generally indicated at H5 is pivoted at II I to a fixed bracket H8. The cylinder has an extended sleeve portion II6 on the opposite end. A piston H9 in the cylinder has a piston rod slidably received in the sleeve, the outer end of which is secured to the lever II3 by a pin I2I. Arm II3, as previously described, is integrally joined to pick-up arm II 2 which is freely journaled on clutch throw-out shaft f. The piston rod has a reduced diameter portion providing an annular valving chamber I22 which is adapted to reciprocate axially within the bore of the sleeve II 6 in response to the movement of the piston. An axial passage I23 connects chamber I22 with the vacuum chamber in the cylinder H5 at all times. The sleeve has ports I24, I25

and I26 opening into the axial boreof same, and

adjustable back-stop I26, and a retracting spring I29. The pedal is so adjusted that the back-stop abuts the floor boards IOI, and the pick-up arm II2 abuts arm H4 when the clutch is in full engagement.

A vacuum supply reservoir I30, having a check valve I 3|, is connected to the motor fuel intake manifold l by a conduit I 32. A manually operated reservoir shut-off valve I33 is controlled by a valve extension handle I34 located on the instrument panel 1". A conduit I35 leads from valve I33 to a central passage I36 in the vacuum control valve unit generally designated as I31, and shown in detail in Fig. '7. The control valve unit comprises two valving pistons I38 and I39 adapted to reciprocate vertically within cylinders I40 and HI respectively. The pistons are urged to seat upon the cylinder shoulders I42 by means of springs I43. Pistons I38 and I39 have transverse passages I44 and I45 respectively and are adapted to communicate with the central passage I36 in certain positions of the pistons as shown in Fig. 7. The pistons are restrained from rotative movement by guide pins I46 extending in the piston slots I41. Cylinders I40 and I H in the valve unit have ports I48 and I49 respectively in transverse alignment with passage I36. Cylinder I39 has a second port I50.

The control valve unit I31 and operating vacuum cylinder unit II5 are connected by three conduits, I61, I68 and I69 connecting the above in respective order as follows; conduit I61 from port I48 to port I24, conduit I68 from port I49 to port I25, and conduit I69 from port I to port I26.

The valve unit I31 is'operatively associated with the accelerator control mechanism. Referring to Fig. 1, piston I38 is capable of being unseated by the arm I5I of lever I52. Said lever is pivoted at I53 and is connected at I54 to the throttle rod 0. The throttle lever m is urged to abut stop n when the throttle is closed, by means of the retracting spring I55. The accelerator pedal p, pivoted at the floor boards I III, has secured thereto a tubular pedal rod I56 which extends forwardly through the dash board, and freely telescopes a rod I51 which is also connected to lever I52 at I54. Rod I51 has an integral depending lug I58 operable axially in the slot I59 (see Fig. 7) of tubular rod I56. A spring I6I is attached to the lug I58 and connected to a corresponding lug on the shoulder I60 of tubular rod I56, to urge this rod' rearwardly. Piston I39 is capable of being unseated by' the dog I 62, pivoted at I63. In normally retracted position of the pedal, shoulder I60 supports the dog I62 in raised condition thereby maintaining piston I39 in unseated condition. When pedal rod I56 is advanced, the dog I62 will drop to the pin I64 by virtue of gravity and the spring I43, at which time the shoulder I60 will abut shoulder I65 on rod I 51, thus insuring a positive forward movement of the throttle rod 0, as shown in Figs. 8 and 9.

The operation of the vacuum power device for shifting gears is as follows. Assume that the shift rods are in neutral position, that the motor is functioning and that the pedal 12 is in fully released position A. In this position, both valve pistons I38 and I39 are in position as shown in Fig. 7 to deliver vacuum from the vacuum reservoir I30 to the cylinder II5. If handle I34 is pushed forward, vacuum will flow from the intake manifold to the cylinder through both the conduits I61 and I68. The path of the vacuum from the reservoir is through conduit I35, passage I36, dividing and entering transverse passage I44 and I45 in the valve pistons, and from them through conduits I61 and I68 respectively to ports I24 and I25 on sleeve II6 of the cylinder. The vacuum entering port I24 will pass into-the annular valve chamber I22 and thence through conduit I23 to the face of the piston where it will act to draw the piston toward the rear end of the cylinder. As the piston reaches mid position in the cylinder the annular valve chamber will appear opposite the port I25 and admit vacuum and convey vacuum from this port .to the face of the piston. The piston is therefore advanced from the forward end of the cylinder to the rearward end in two stages.

During the first stage of the pistons move-' ment, or from the front end of cylinder I I5 to the middle thereof, the piston, acts through pickup arm I I2 to swing the clutch throughout shaft 1 suflicient to disengage the clutch. During the second stage of its rearward movement, the piston acts through the connecting rod 80, rack teeth 19 and gear sector." to move the shift rod frame 56 from its rearward position to its forward position in the transmission. The disengagement of the clutch prior to the advanceof the frame 56 is provided: by the lost motion connection between the rack teeth I9 and gear sector18 as previously described. Therefore when the motor is functioning with the control rod 34 pushed in and the accelerator in released position at A, the piston will be shifted rearwardly the full distance in the cylinder, the clutch will be disengaged, and the shift rod frame will be at the forward.- end of its stroke in position to shift rods to'the desired change of speed.

At this point, the selector arm I 01 on the steering column may be adjusted to low gear opposite numeral 1, or any one of the control buttons in the modification in Figures 24 to 29 inclusive may be pushed if this modification is utilized. This causes a latching dog carried on the shift rod frame to interlock with the proper shift rod for shifting the transmission into .low" speed. Upon movement of the accelerator pedal from A to B. dog I62 will fall as indicated in Fig. 8 and valve piston I39 will cut off the feed of vacuum through conduit I68 and open the conduit I69 to atmosphere through ports I50 and 2I3. This subjects the annular valve chamber I22 and the face of the piston II9 to atmospheric pressure. Since pressure is now balanced on opposite sides of the piston, the piston will move forwardly in the cylinder due to the expansion of the conical cylinder spring and the clutch spring e. When the accelerator pedal is in 3" position, the piston will not be able to more forwardly any further than its center position in the cylinder. Further forward movement will bring annular valve chamber I22 into communication with port I24 which is still subject to vacuum and this will cause the piston to reverse its movement. The piston will therefore fioat between the two extremes of its movement. The movement of the piston to its middle position will cause the shift rod frame to move rearwardly and shift the transmission into "low" gear. The clutch, however, is still disengaged.

Upon further depression of the accelerator pedal to C"-D, the shoulder I60 abuts shoulder I65 and accelerator movements are imparted to throttle rod .0. Dog I 5| is therefore pivoted clockwise and valve piston I38 falls and seats as indicated in Fig. 9. This cuts off the flow 01' vacuum through conduit I61 and port I24 and instead vents this conduit and this port to atmosphere through slot I41 and port 2I4 in the valve control unit. The face of the piston is imcontrol dog I SI and I62 to rise and unseat the valve pistons I38 and I39 respectively. This will cause delivery of vacuum through both conduits i6! and I68 to the cylinder and piston I I9 therein will advance completely to the rear in two stages. In the meantime, the manual selector on the steering column or dash panel has been regulated for "second gear. Up'on depression of the accelerator pedal again to positions C, D and further, this piston is caused to return to its forward position in two stages of movement, the first stage causing the returnof the shift rod frame with the proper shift rod for second gear, and the second stage causing engagement of the clutch for propelling the motor vehicle in second gear. It is obvious that the shifting operations for the other speeds is due in a like manner to that above described.

In the foregoing vacuum control of my shifting mechanism, the vacuum control valve unit 5 232 and I31 is actuated by manual regulation of the accelerator pedal for all speeds. In the modification shown in Figs. 30 to 39, the vacuum control valve unit 22I is actuated by mechanical means regulated automatically by the speed of the vehicle, for all speeds ahead.

The valve unit MI is responsive to the initial movement of the acceleratorpedal' p by arm 2I5 pivoted thereto and extending forwardly engaging a slot in a valve plunger 2I'8. The pedal has a pickup shoulder 2 I6 registering with a corresponding shoulder on arm 2I5. When pedal p is advanced to position C, shoulder 2I6 will move far enough so that the arm 2I5 will fall to stop 2I1, thus permitting plunger 2I8 to descend.

Thereafter the pedal will be free to continue forwardly without effecting the valve unit 22!. On the return pedal stroke, shoulder 2 I6 will pick up arm M5 at position and again raise said arm and plunger.

The valve unit 22I is shown in detail in Fig. 34. The plunger 2 I 8 has a stem portion 2 I 9 extending downward through the chamber closure 236, and secured to a piston 220 adapted to reciprocate in the vertical valve chamber 224. The piston has two spaced annular peripheral passages 222 and 223, and an integral squared depending plunger 225 extending through a square aperture in the bottom of the valve chamber. A roller 226 is journaled to the lower extremity of the plunger 225. I

A spring 221 interposed between the piston and closure 236, urges the piston downwardly when the pedal arm 2I5 is released. Located in the walls of chamber 224 are ports in pairs in transverse alignment, namely, 228 with 229, 230 with 23I, 232 with 233, and 234 with 235. Conduit I35, leading from the vacuum reservoir, is connected to ports 229 and 233. The vacuum cylinder unit H and the conduits I61, I68 and I69 connected thereto are similar to the vacuum operated device described above. Conduit I61 is connected to ports 226 and 236 in the valve control unit 22I. Conduit I68 is connected to port duit I69 is connected to port 235.

The val e unit MI and the gear shift mechanism pre iously described are rendered responsive to the speed of the vehicle by regulating mechanism driven from a moving part of the vehicle. In the embodiment of the invention described herein, this mechanism comprises a speed responsive device, such as the governor 243, operatively coupled to the propeller shaft 2' by sprocket chain 238 encircling the sprocket 231 keyed to the propeller shaft and sprocket 239 keyed to a stub shaft 240 which drives the governor. Arms of a conventional governor indicated as 243 are pivotally connected between one of the stub-shaft collars. 242 and a freerunning collar 244, the last mentioned collar being restrained axiallyin a bearing on the rear extremity of a selector and .valve actuating rod 245. It is apparent that any other speed responsive device could be employed in place of the conventional governor 243.

The actuating rod 245 is adapted to reciprocate axially in the bearings 246 of a. supporting plate 241 secured to frame members 70. A selecting cam block 248 is bored from end to end to receive the enlarged portion 249 of the rod, and is positioned axially on said rod by adjustment nuts 256. The block has lateral flanges 25I free to slide along plate 241, these flanges serving to maintain an upright position of the cam block. The top of the cam block has three flat horizontal cam faces, 252, 253 and 254, for low, "intermediate and high speeds, respectively, and arranged in step-down formation.

Operating linkages connecting the shift rod frame in the transmission with the automatic controller comprise a plunger 255, reciprocable in a vertical bearing 251, is provided with a roller 256 at the lower extremity. A link 258 connects the upper end of the plunger with an arm 259. Arm 259 and lever 96' are integrally formed on the hub 266 and keyed to the spindle 94', corresponding to spindle 94 in Figs. 13 and 16. A retracting spring 26I is secured at one end to stop 2" and at the other end to lever 96'.

The valve unit 22I is operatively connected to rod 245 through elements swingable about a fixed spindle 262 affixed to the motor case. Upon the spindle is freely mounted a cam sector 263 and a gear sector 264, the latter having an arcuate slot 265. A stud 266 is fixed in the cam sector and projects in the gear sector slot effecting an overrunning rotative connection between these sectors. The gear sector meshes with the rack 261 on the forward end of the operating rod 245. A spring 268 is attached to sector 264 and secured to a fixed stud 269, for the purpose of retracting the operating rod. The cam sector has an arcuate face 210 and spaced cams 21I and 212 thereon. The'cam sector is so spaced from the valve control unit 22I that piston 220 is seated in chamber 224 when the roller 226 contacts the sector face 2W3.

To manually selectively determine forward, neutral'or reverse driving conditions a controller may be secured to the steering column comprising a bracket sector 213 having positioned thereunder an arm 214 fixedly attached to shaft 39. Linkages I04 and 98 operating-from shaft 99 are connected to the shifting mechanism lever 96' in the same manner as shown in Figs. 1, 2 and 3. A pawl 216 having a pointer is hinged on a pin 211 between ears of a lug integral with arm 214. The outer end of the pawl is urged upward by a spring 218, as shown in Fig. 32, causing the pawl to abut the fiat lug face 219, thus insuring a clearance between the pawl and sector surface, so that the arm is free for movement of speeds ahead. The pawl portion lying over the sector is beveled at 280 to permit it to ratchet over the sector teeth 28I struck out from bracket 213 as shown in Fig. 33. References N and "R are marked opposite the teeth 28I to indicate neutral and "reverse. The pointed inner end of the pawl serves to indicate the speed for which the shifting mechanism selecting elements are positioned.

Manual operation of arm 214 is only required for "neutral and reverse and for changing from either of the same to the sector indication 1 for speeds ahead. When pointer 216 is opposite indication 1 and forward speeds are made by the vehicle, the pointer will operate automatically from 1 to 3 andback as the selector v cam roller 256 contacts the block cam faces 262 to 254 and back respectively, by virtue of the retracting spring 26I which functions to maintain contact of the plunger roller with the cam faces, when speeds within the above range are employed.

As the roller is in contact with cam face 252 for "low, or first speed ahead, as shown in Figs. 30 and 31, it is apparent that plunger 255 must be drawn upward against tension of spring 26I in selecting for neutral and reverse; therefore, for the latter selections, arm 214 must be moved manually to or B. when the pawl will ratchet over a tooth 28I and withhold the arm in register with the indication selected. The arm may be released from either of the latter positions by a downward pressure on the outer end of the pawl, when spring 26I will return the arm to position "1 on the sector.

The full line position of the elements in Figure 30 illustrates a condition of the automatic con.- troller when the motor vehicle is at rest and the motor inoperative and the gears in the transmission engage in low gear position. To shift the gears in the transmission to neutra position, manual selector 216 on the steering column is carried over the tooth 28I opposite N and interlocked therewith upon release of manual pressure on the outer end of the selector 216. Complete depression and full release of the clutch pedal will now cause the shift frame in the transmission to move forward and shift the rods to neutral position and then move to its rearward position without effecting movement of any of the shift rods.

Assuming the apparatus in neutral condition as above described, operation of the motor will subject the reservoir I30 to suction. Upon pushing valve handle I34 flush with the dash panel suction is transmitted to valve unit 22I where by virtue of the raised condition of the valve piston 22!], the suction divides and flows to the cylinder II5 by the two conduits I61 and I68. This causes the two-stage movement of the piston II9 described in earlier embodiments of the invention. In the first stage the clutch is disengaged and in the second stage the rod shift frame in the transmission performs its forward stroke. Either at this time, or earlier if desired, selector handle 216 on the steering column is swung to low gear opposite indication 1" on bracket 213. This rotates the cam selector in the transmission and interlocks the proper shift rod with the movable frame for causing"low gear engagement in the transmission when the frame returns to its rearward position. 4

Depression of the accelerator pedal from A to position "C will lower arm 2I5 and drop valve plunger 22!] in the valve unit to the position shown in Fig. 36. In this position, the delivery of vacuum through both conduits I61 and I68 is cut off and conduit I69 is opened to atmosphere through port 234. This causes a complete forward advancement of the piston which shifts gears into low and engages the clutch. The motor vehicle commences to move in low gear. Further depression of the accelerator pedal increases the speed of the motor vehicle and the elements of the governor 243 will distend thereby causing rod 245 and associated cam block 248 to move rearwardly. When a predetermined speed of the vehicle is attained, the cam face 252 recedes from under roller 256 and the latterfalls to cam face 253 as shown in Fig. 36. This movement will be transmitted by way of rods 255 and 256 to the cam member 86 in the transmission and cause the latter to assume a position which will interlock the frame with the proper shift rod for shifting the gears into second speed. During this movement of the rod 245, gear sector 264 will be rotated counter-clockwise but will not impart such movement to the cam sector 263 because of the lost motion connection between these sectors provided by the slot 265. However, as the motor vehicle increases in speed and produces further rearward movement of the rod 245; the cam sector 263 will be picked up and rotated until it assumes the position in Fig. 37.

In this position valve plunger 220 is raised and opens communication between vacuum line I35 and cylinder conduits I61 and I68, thereby causing the piston II9 to move rearwardly in two stages. This disengages the clutch and advances the rod shift frame to its forward position in the transmission thus disengaging the low gears and interlocking with the proper shift rod for accomplishing the shift to second gear speed. The continuer acceleration of the motor vehicle even after the low gears are disengaged will cause further rearward movement of the rod 245, thus imparting further counter-clockwise movement of cam sector 263. Valve roller 226 will now descend to came face 210 between the cam portions 2" and 212 before the selector roller 256 leaves cam face 253. This condition is shown graphically in Fig. 38. The descent of the valve plunger 220 will cut off delivery of vacuum to the cylinder and piston I I9 will return to its forward position, first causing second" gear engagement and then clutch engagement of the propeller shaft to the motor unit.

The shifting operation to high speed is obviously accomplished in the same manner as for low and second" speeds, leaving the elements in the position shown in Fig. 39. During all these automatic movements-from "low to high speeds, the selector handle 216 on the steering column follows the movement of the cam member 86 in the transmission and indicates to the driver the various conditions of the automatic apparatus.

When the vehicle is slowed down, the governor elements contract and control rod 245 will move forwardly and impart clockwise movement to gear sector 264. Because of the lost motion connection between gear sector 264 and cam sector 263, the vehicle is allowed to slow down considerably before gear and clutch disengagement take place. Continued deceleration will cause the valve plunger 220 to rise and fall successively over cams 212 and 2H and also cause the selector roller 256 to mount the stepped cams on the block 248. Due to the slot 265 in the gear sector 264, the movement of the cam selector i63 will follow slightly behind the step by st lifting movements of the selector roller 256m '1 bus both in acceleration and deceleration, the change of gear is selected before disengagement of the clutch and shifting of gears is effected.

In the event of failure of the automatic controller, it is apparent that the shifting mechanism may be operated by the clutch pedal for all speeds ahead, as well as for neutral and reverse" by timing the pedal stroke in accordance with the gear selection indicated by the pointer 216 on the steering column.

What I claim:

1. In a variable speed transmission gear mechanism for an automobile, a pair of rods positioned in spaced side by side relationship, means supporting said rods for slidable :lengthwise movement, a gear shifting member secured to one of said rods, a pinion rotatably supported between said rods, r'ack teeth on the adjacent sides of said rods engaging with said pinion and adapted upon movement of one of said rods to impart equal and opposite movement to the other rod, a rectangular frame having perforations in two opposite ends thereof in which the extremities of I said rods are slidably-disposed, means mounting said rectangular frame for reciprocable movement parallel to the direction of movement of said rods, a latching plate for each rod slidably mounted on one end of said frame and adapted to engage in a recess in its respectve rod when the frame is moved to a predetermined position, spring means carried by said frame yieldingly acting to withdraw said latching plates from engagement in said recesses, manual control means for separately moving said plates against the resistance of said springs into the recesses in said rods, means carried by said rods adjacent the other end of the frame and adapted to extend into the path of movement of saidend of the frame, said last mentioned end of the frame adapted when the frame is moved in one direction of its movement to abut said means on-said l5 rods and cause the rods to. be shifted thereby.

2. In a variable speed gear transmission for an automobile, a rectangular frame having'aligned apertures in two opposite ends thereof, a p1u-. rality of gear shift rods mounted in the plane of 20 said frame and having their opposite ends extending through the apertures in the frame, means supporting said rods for lengthwise slid-, .able movement, means supporting said frame for lengthwise reciprocable movement, and separate 25 means for each rod carried by one end of said frame and adapted to releasably look its respectiverod to the frame for joint lengthwise movement together in one direction to shift a gear in the transmission into mesh with another gear,

30 and means carried by the other end of said frame adapted to engage any such rods thus shifted upon movement of the frame in the other direction and shift a gear out of mesh with another Bear in the transmission.

5 8. In a variable speed gear transmission for an automobile, a gearshift rod, a second gear shift rod, a companion rod associated with each of said gear shift rods, means supporting said rods for lengthwise movement parallel to one 40 another, means operatively associating each of said gear shift rods with its companion rod so that upon lengthwise movement of one of the rods the other will be moved simultaneously in the pposite direction, said rods in neutral gear :5 ed position being disposed substantially opposite one another, a rectangular frame apertures in the opposite ends thereof in which the opposite ends of said rods are slidabiy disposed, means for bodily moving said frame 59 parallel to the path of movement of said rods from one position to another, one end of the frame adapted upon movement of the frame from one of said positions to the other to engage any one of said rods in gear engaged position g and move the same until the rods are disposed- 'flllhltantinllv equally opposite one another in neutral position, latching means for each shift rod carried by the other end of the frame adaptable -in said other position of the frames movement to lock its respective shift rod to said frame for joint movement therewith.

4. A speed change gear mechanism for an automobile comprising, in combination, a plurality of gear shift rods arranged in parallel relationship and adapted to bodily move in parallel paths to shift the gears, a rectangular frame mounted for reciprocating movementin a path parallel to and adjacent to the paths of movement of the rods, means carried by one end of the frame for interlocking each rod with the frame for joint travel with the frame in one direction of its movement, control mechanism for selectively operating said rod and frame interlocking means carried by said end of the frame, means carried by each shift rod on the inside of the frame adjacent to theopposite end'of the frame adapted to project into the Path of travel of said end of the frame and be engaged and shifted thereby when the frame moves in the opposite direction.

5. Gear shift control mechanism for a motor vehicle comprising, in combination, a variable gear transmission, a clutch operable to couple the transmission to the power unit of the vehicle to receive driving impulses therefrom, a pair of gear shift rods in said transmission mounted for lengthwise movement in parallel paths, means coupling said rods together so that upon movement of one rod in one direction the other rod will move equally in the opposite direction, a rectangular .frame mounted for reciprocating movement in said transmission along a path parallel to and adjacent to said rods,'means operatively coupling said fram .With said clutch so that the frame is movable"from a position in the transmission corresponding to that when the clutch is fully engaged .to a position in the transmission when the clutch is fully disengaged, latching means for each shift rod carried by one end of said frame adapted to lock its respective shift rod to the frame when the latter is in the position corresponding to that when the clutch is in-the fully disengaged position and to move said shift rod jointly with the frame as it moves in response to the movement of the clutch to fully engaged position, control means selectively operable for actuating said latching means, the other end of said frame adapted when the clutch moves toward fully engaged position to contact rods thus shifted and return them to initial operating position..

ROBERT N. VAN BUSKIRK. 

